During testing of electronic circuits there arises a necessity for monitoring voltage or current pulses in the circuits of the unit under test without making electric contact with the circuit elements. Such a need exists, for example, if the unit has a protective isolating coating which must not be broken or if current pulses in the unit circuits must be monitored without opening said circuits. In such cases non-contact measuring devices are used. These devices are provided with a sensing means responsive to electromagnetic field variations arising due to variation of currents and voltages in the unit circuits. The sensing means converts the field variations into an electrical signal, the magnitude of which depends on the amplitude of the electrical pulse appearing at the circuit point near which the sensing means is placed. This electrical signal is supplied to the input of an indicator unit which in some way or other responds to the magnitude of said signal. This permits monitoring of electrical pulses in the circuits of electronic units without making electric contact with the circuit elements. Monitoring of voltage pulses is achieved by the use of devices wherein the sensing means is a capacitive transducer responsive to the electric component of electromagnetic field. Monitoring of current pulses is achieved by the use of devices wherein the sensing means is an inductive transducer responsive to the magnetic component of electromagnetic field.